A Gartner Research note written by Litan explains that in the past few months, Gartner has heard from many banks around the world that rely on one-time-password authentication systems. Accounts at these banks have been compromised by man-in-the-middle attacks -- the report uses the term "man-in-the-browser" -- despite the use of two-factor security.

One technique that the fraudsters have been using to bypass security controls is call forwarding.

"[B]anks that rely on voice telephony for user transaction verification have seen those systems and processes compromised by thieves who persuade
telecom carriers to forward legitimate user phone calls to the thief's cell phone," the report says. "These targeted attacks have resulted in theft of money and/or information, if the bank has no other defenses sufficient to prevent unauthorized access to their applications and customer accounts."

A man-in-the-middle attack involves using software or hardware to intercept network traffic then send it to its destination so that the information can be used without the knowledge of the sender or the intended recipient.

In an e-mail, Litan said that the attacks have involved the Zeus Trojan and other customized malware.

The malware sometimes uses anti-forensic capabilities that re-write account balances in the user's browser, so that the user believes his or her bank account has the funds it should, even through it is empty.

According to the Internet Crime Complaint Center, which issued a warning about attacks on commercial bank accounts in November, total losses as of October amounted to about $100 million so far this year.

Published: 2015-03-31The build_index_from_tree function in index.py in Dulwich before 0.9.9 allows remote attackers to execute arbitrary code via a commit with a directory path starting with .git/, which is not properly handled when checking out a working tree.